nett bluemax™ scr system...property unit siemens (1999) din v 70070 name aqueous urea solution no...

V1.4

Nett Technologies Inc. 2-6707 Goreway Drive, Mississauga, Ontario

Canada L4V 1P7

tel: 905.672.5453

fax: 905.672.5949

e-mail: [email protected]

web: http://www.nett.ca

Nett

BlueMAX™

SCR System

2

Contents

Introduction ................................................................................................................. 3

What is Selective Catalytic Reduction? .......................................................................... 4

How the Nett BlueMAX™ System Works ....................................................................... 5

Nett BlueMAX™ System Specifications .......................................................................... 6

Nett BlueMAX™ System Standard Models and Sizing Charts .......................................... 7

Urea Replenishment and Consumption ......................................................................... 8

Urea Handling & Storage .............................................................................................. 9

Maintenance Requirements........................................................................................ 10

Parts .......................................................................................................................... 23

Troubleshooting ......................................................................................................... 24

3

Introduction

Nitrogen oxides (NOX), one of the most troublesome emissions from the diesel engine, is the

generic term for a group of highly reactive gases, all of which contain nitrogen and oxygen in

varying amounts. The main component of NOX, nitric oxide (NO), is colorless and odorless.

However, another component of NOX, nitrogen dioxide (NO2) along with particles in the air

can often be seen as a reddish-brown layer over many urban areas.

Nitrogen oxides form when fuel is burned at high temperatures, as in a combustion process.

The primary manmade sources of NOX are motor vehicles, electric utilities, and other

industrial, commercial, and residential sources that burn fuels.

NOX emission reductions are needed because NOX leads to formation of ozone and

secondary particulate emissions (PM2.5) in the atmosphere. Ozone is a powerful oxidant,

and exposure to ozone can result in reduced lung function, increased respiratory symptoms,

increased airway hyper-reactivity, and increased airway inflammation. Exposure to ozone is

also associated with premature death, hospitalization for cardiopulmonary causes, and

emergency room visits for asthma.

Nett Technologies designed the BlueMAXTM

SCR system to effectively control NOX emissions

from medium- and heavy-duty diesel engines in such applications as on-road, non-road and

stationary. The exhaust temperatures needed for proper operation are typically

encountered in most medium- and heavy-duty diesel engine applications. The Nett

BlueMAXTM

system typically provides a reduction in NOX emissions in the range of 65 to 90%

under transient diesel engine conditions and over 90% in steady-state operation.

4

What is Selective Catalytic Reduction?

Selective Catalytic Reduction—commonly referred to as “SCR”—is a proven technology

capable of reducing diesel NOX emissions using compounds such as ammonia or urea, which

are injected upstream of the SCR catalyst. In urea-based systems, the injected urea solution

evaporates in the hot exhaust gas and decomposes producing ammonia. Through catalytic

reactions with ammonia, NOX emissions are reduced to harmless products including

nitrogen and water vapor.

The process of urea decomposition is typically described by the following hydrolysis

reaction:

CO(NH2)2 + H2O → 2NH3 + CO2

In practice, the decomposition of urea proceeds through two separate reactions, involving

an isocyanic acid (HNCO) intermediate. In the first reaction, HNCO and one molecule of

ammonia are formed by thermolysis of urea, followed by hydrolysis of the HNCO with the

formation of second NH3 molecule:

CO(NH2)2 → NH3 + HNCO

HNCO + H2O → NH3 + CO2

A possible alternative path of urea decomposition is a direct thermolysis with the formation

of an ·NH2 radical:

CO (NH2)2 → 2 ·NH2 + CO

This thermal decomposition is confirmed by an evidenced formation of CO during SCR

processes with urea. The ·NH2 radical can then react with NO as follows:

·NH2 + NO → N2 + H2O

How the Nett

The Nett BlueMAXTM

through chemical reactions with a reducing agent (urea). The urea solution is carried

onboard tank and injected upstream of the SCR catalyst. The main components of the Nett

BlueMAX™ system include the SCR catalytic converter, the urea dosing system (UDS), and

the urea tank (Figure 1). The urea control strategy relies on a NO

measurement by a sensor positioned upstream of the SCR converter. Based on the NO

sensor signal, in combination with an engine mass air flow sensor and temperature sensors,

the necessary urea dosing rate is calculated by the control software.

The NOX sensor-based strategy makes the system very su

time-consuming calibration (such as through engine mapping) is necessary, and the system

can be installed on a wide range of diesel engines, including mechanical engines.

Urea (in the form of a 32.5% water

the necessary amount of urea is metered by a precise dosing pump. The urea solution is

introduced to the exhaust pipe upstream of the SCR catalyst through an inje

Urea atomization is supported by compressed air supplied by a compressor.

How the Nett BlueMAX™ System Works

TM system is a urea-SCR system. NOX is reduced over the SCR catalyst

through chemical reactions with a reducing agent (urea). The urea solution is carried


system include the SCR catalytic converter, the urea dosing system (UDS), and

the urea tank (Figure 1). The urea control strategy relies on a NO

measurement by a sensor positioned upstream of the SCR converter. Based on the NO

, in combination with an engine mass air flow sensor and temperature sensors,

the necessary urea dosing rate is calculated by the control software.

Figure 1: Nett BlueMAX™ System Schematic

based strategy makes the system very suitable for retrofit applications. No

consuming calibration (such as through engine mapping) is necessary, and the system


Urea (in the form of a 32.5% water-based solution) is stored in the urea tank. From the tank,


introduced to the exhaust pipe upstream of the SCR catalyst through an inje


5

is reduced over the SCR catalyst

through chemical reactions with a reducing agent (urea). The urea solution is carried in an


system include the SCR catalytic converter, the urea dosing system (UDS), and

the urea tank (Figure 1). The urea control strategy relies on a NOX concentration

measurement by a sensor positioned upstream of the SCR converter. Based on the NOX

, in combination with an engine mass air flow sensor and temperature sensors,

itable for retrofit applications. No

consuming calibration (such as through engine mapping) is necessary, and the system


based solution) is stored in the urea tank. From the tank,


introduced to the exhaust pipe upstream of the SCR catalyst through an injection nozzle.


6

Nett BlueMAX™ System Specifications

Urea Dosing System

Urea Pump and Electronic Control Unit (ECU)

Mechanical Data

Maximum capacity 7.5 L/hr 1.98 gal/hr

Air supply pressure 0.6-1.2 MPa 87.02-174.05 psi

Air consumption rate 20-25 L/min 5.28-6.6 gal/min

Working temperature -11 to +85 °C 12.2 to 185 °F

Storage temperature -11 to +85 °C 12.2 to 185 °F

Accuracy and repeatability +/- 1% +/- 1%

Urea solution temperature -5 to +50 °C

(peak 85 °C)

23 to 122 °F

(peak 185 °F)

Maximum filter dimension for air and urea

(microns) 100 100

Electrical Data

System supply voltage (VDC) 24

Range of supply voltage (VDC) 9-32

Maximum current at 24 V (A) 7.6

Maximum power consumption (W) 150

Compressor (BlueMAX™ 100 Models Only)

Mechanical Data

Maximum pressure 0.69 MPa 100.08 psi

Air flow (l/min @0.7 MPa) 26.5 L/min @ 0.7 MPa 7 gal/min @ 101.5 psi

Max. ambient air temperature 40 °C 104 °F

Min. ambient start temperature 10 °C 50 °F

Electrical Data

Motor rated power (hp) 1/3

Motor voltage (VDC) 24

Power at rated load (W) 440

Current at rated load (A) 18.5

Starting current (locked rotor, A) 122

Urea Tank

Capacity (liters) 25, 35, 45, 55, 65, 85, 100

Urea Solution 32.5% water based urea solution (according to DIN70 070)

7

Nett BlueMAX™ System Standard Models and Sizing Charts

Standard models and sizing charts for the Nett BlueMAX™ system are listed in Table 1. Sizing

for particular engines and applications should be consulted with our office before ordering.

Table 1: Standard Models and Sizing Chart

Model Max. Engine Power

BlueMAX™ 100 BlueMAX™ 200 kW hp

GL5100 GL5150 75 100

GL5200 GL5250 110 150

GL5300 GL5350 150 200

GL5400 GL5450 185 250

GL5500 GL5550 225 300

GL5600 GL5650 260 350

GL5700 GL5750 300 400

GL5800 GL5850 335 450

GL5900 GL5950 370 500

GL – BlueMAX™ SCR System

8

Urea Replenishment and Consumption

The Nett BlueMAX™ system requires that aqueous urea solution (in the form of a 32.5%

water-based solution) be carried in an on-board storage tank and that it is periodically

replenished. Table 2 gives the specifications of aqueous urea solution for SCR application.

Table 2: Specifications of Urea Solution for SCR Application

Property Unit Siemens (1999) DIN V 70070

Name Aqueous urea solution NOx reduction additive

AUS 32

Urea content % wt. 32.5 ±0.5 31.8 – 33.3

Density at 20°C g/cm3 1.085

a 1.0870 – 1.0920

pH 9 – 11 -

Appearance Colorless Colorless liquid†

Point of crystallization °C/°F -11/12.2 -11†/12.2†

Refractive index @20°C - 1.3817 – 1.3840

Alkalinity as NH3 (max.) % 0.4 0.2

Carbonate as CO2 (max.) % 0.4 0.2

Biuret (max.) % 0.4 0.3

Formaldehyde (max.) mg/kg - 10

Insolubles (max.) mg/kg - 20

Phosphate, PO4 (max.) mg/kg - 0.5

Calcium (max.) mg/kg 1b 0.5

Iron (max.) mg/kg - 0.5

Copper (max.) mg/kg - 0.2

Zinc (max.) mg/kg - 0.2

Chromium (max.) mg/kg - 0.2

Nickel (max.) mg/kg - 0.2

Magnesium (max.) mg/kg - 0.5

Sodium (max.) mg/kg - 0.5

Potassium (max.) mg/kg - 0.5

Viscosity (dynamic)

@25°C mPa·s - ~1.4†

Thermal conductivity

@25°C W/mK - ~0.570†

Specific heat @25°C kJ/kgK - ~3.40†

Surface tension (min.) mN/m - 65†

† informaSve only (not normaSve)

a – at 15°C

b – mg/dm3

Source: DieselNet

Urea consumption can vary from 1 – 5% (by vol.) relative to diesel fuel consumption

(approximately 0.9%, relative to fuel consumption, of 32.5% urea solution is consumed per

1g/bhp-hr of NOX that is reduced).

9

Urea Handling & Storage

Urea is a synthesized chemical that contains ammonia and carbon dioxide. In the solid form

it contains the highest nitrogen content of any non-hazardous commercially produced

material. Approximately 95% of all urea consumed in the U.S. is used as either an

agricultural fertilizer (85%) or as a component of formaldehyde resin production (10%).

In general, urea is considered a non-hazardous and non-toxic material. As with all

chemicals, urea should be treated with respect, caution and the proper personal protective

equipment (PPE).

PPE should be used to protect against accidental contact with the product. The use of

chemical resistant gloves and face shield are the recommended minimum.

Skin: Short term contact with skin causes no injury. Prolonged contact can cause a

rash or minor irritation. Washing with soap and water is sufficient to clean the

contacted area. Clothing that has been exposed should be removed as soon as

possible. Clothing can be cleaned using a normal washing cycle.

Eye: Chemical goggles and/or face shield should be worn when handling urea

solution to avoid accidental contact with eyes. Urea solution is somewhat basic

which will cause short-lasting eye irritation. Any contact should be immediately

flushed from the eye using standard eyewash procedures.

Please refer to the attached MSDS for further details and instructions on safe handling

procedures.

According to DIN V 70070, urea solutions should be stored in tanks made of austenitic Cr-Ni

or Cr-Ni-Mo steels (copper or galvanized steel tanks should not be used). To minimize urea

crystallization and hydrolysis, the optimum storage temperature is 25°C.

10

Maintenance Requirements

As the equipment owner, you are responsible for performing the required maintenance

described below on your Nett BlueMAX™ System. Nett Technologies recommends that you

retain all maintenance records and receipts of maintenance expenses and urea purchases. If

you do not keep your receipts or fail to perform recommended scheduled maintenance as

listed below in Table 3, Nett Technologies may have grounds to deny warranty coverage.

The most important maintenance that can be carried out to keep the BlueMAX™ system

operating properly is engine maintenance. Wear to engine valves or rings can cause high

lube oil consumption. This oil will exit the engine through the exhaust system, and it can

irreversibly deactivate the catalyst.

Table 3: Maintenance Requirements

Note: Servicing should be done for which ever service time comes first (i.e. hours or monthly)

The following are step-by-step instructions for performing the scheduled maintenance

services as mentioned in Table 3.

# Service Times Action Required

1 Daily

(while in operation)

• Observe urea alarm box (mounted on cab) for

indicator codes

• Report any alarms to Nett Technologies

*See Troubleshooting section for Error Codes*

2 Every 100hrs/bi-weekly

• Drain air tank inlet filter by depressing spring

loaded pin

• Drain air tank

3 Every 250hrs/monthly • Clean air compressor inlet filter

4 Every 500hrs/3 months • Inspect urea injection nozzle and if necessary clean

by soaking in tap water

5 Every 1000hrs/6 months • Drain urea tank and flush using clean tap water

• Inspect urea filter and clean using tap water

6 Every 1500 hrs/9 months • Change compressor brushes at 1500 hrs of

operation and at 800 hrs after

11

1) Daily Operations (While in Operation)

i. Locate the urea alarm box mounted on the vehicle cab (see Figure 2 below).

ii. Read error code display (outlined in Figure 2).

iii. Call Nett Technologies to report any error codes.

iv. Once the error has been rectified, the error code will disappear from the alarm box

display.

Figure 2: Urea Alarm Box Display

12

2) Every 100 Hours or Bi-Weekly

i. Locate the air tank on the vehicle.

ii. At the bottom of the air tank, locate the brass drain plug & wing nut fitting (outlined

in Figure 3).

iii. Loosen the wing nut by approximately one half turn.

Figure 3: Air Tank Indicating Wing Nut and Water Separator Location

iv. Air will begin to drain once the wing nut has been loosened.

v. Once draining is complete, tighten the wing nut.

vi. Locate the Air Filter/Water Separator unit attached to the air tank inlet as shown in

Figure 3.

vii. Drain water separator unit from air tank by depressing the spring loaded pin located

at the bottom of the water separator canister. Remove any liquid collected (see

Figure 4).

Figure 4: Drain Valve on Water Separator Unit

Loosen Wing Nut

Water Separator

Press pin into canister to drain liquid

13

2) Every 100 Hours or Bi-Weekly continued…

viii. Unscrew the canister of the water separator unit to expose air filter.

ix. Check the condition of the air filter of the water separator unit. If air filter is dirty

then replace it. See Figure 5 for reference.

Figure 5: Air Filter/Water Separator

Example of a clean air filter

in a water separator unit

14

3) Every 250 Hours or Monthly

i. Locate the air filter assembly on the air compressor motor (see Figure 6).

ii. Remove the air filter assembly by unscrewing it from the air compressor motor.

Figure 6: Air Compressor Motor

iii. Snap off the cover of the air filter assembly to expose the air filter as shown in Figure

7.

Figure 7: Air Filter Assembly

iv. Remove the air filter from within the assembly as shown in Figure 8.

Figure 8: Disassembled Air Filter Assembly

Air Filter assembly

Filter

Cover

15

3) Every 250 Hours or Monthly continued…

v. Clean the air filter using compressed air using Figure 9 as a reference.

Figure 9: Dirty Air Filter

vi. Once the filter is clean, return it into the filter assembly, and secure it by re-installing

the cover.

vii. Re-install the air filter assembly by threading it onto the air compressor motor.

Air filter should be cleaned

16

4) Every 500 Hours or 3 Months

i. Locate the urea injection nozzle on the SCR unit as shown in Figure 10.

Figure 10: Typical SCR Installation

ii. Unscrew the bolt fastening the injection nozzle to the SCR unit.

iii. Remove the injection nozzle from the SCR unit as per Figure 11.

Figure 11: Injector Nozzle Assembly

iv. Inspect the injector for urea build up (urea crystals) around the nozzle and within the

four holes of the injector tip as shown in Figure 12.

v. If a build up exists, place injector nozzle in water to dissolve urea crystals. Note:

Warmer/hotter water will dissolve urea crystals quickly.

iii. Remove nozzle from the SCR

ii. Remove the bolt securing the nozzle to the SCR unit

Example of an injector nozzle on a typical SCR

unit

17

4) Every 500 Hours or 3 Months continued…

Figure 12: Injector Nozzle with Tip Detail

vi. Once the nozzle is cleaned, insert it into the SCR and fasten by tightening the bolt

onto the injector port (see Figure 13). Be sure to align the nozzle pin with the slot on

the injector port to ensure injection occurs in the exhaust flow direction.

Figure 13: Injector Nozzle Reassembly onto SCR

Nozzle Tip Detail

Insert injector nozzle into SCR. Align the pin

and slot

18

5) Every 1000 Hours or 6 Months

i. Locate the urea tank mounted on the vehicle.

ii. Drain urea by removing drain plug located at the bottom of the urea tank as shown

in Figure 14. Use a clean container to collect urea to be re-used when refilling

Figure 14: Urea Tank

iii. Pour tap water into urea tank to flush out remaining urea solution.

iv. Once drained out, flush again with tap water to ensure tank is flushed completely.

v. After flushing, reinstall the drain plug at the bottom of the urea tank.

vi. Re-fill the urea tank with urea solution.

vii. Remove the urea suction lance from the top of the urea tank by unscrewing the bolts

securing it to the mounting flange as shown in Figure 15.

Figure 15: Urea Suction Lance Components

Drain Plug

Lance Guard

Urea Suction Lance

Mounting Flange

19


viii. Check the urea filter located at the bottom of the urea suction lance to ensure it is

not clogged with particles. See Figure 16 and 17 for location of filter.

Figure 16: Urea Suction Lance

Figure 17: Urea Filter

ix. If the urea filter is clogged, it must be replaced.

x. Re-insert the lance into the urea tank.

xi. Fasten the lance to the mounting flange using the original bolts.

Clean Filter Detail

6) Every 1500 Hours or 9 M

i. Locate the two access panels for the brushes on either side of the air compressor

housing as shown in Figure 1

ii. Remove the access

iii. Remove the machine screw

wires to the copper electrical contact.

iv. Lift and disengage the retaining spring to allow for the removal of the

(also labeled in Figure 1

Hours or 9 Months

Locate the two access panels for the brushes on either side of the air compressor

housing as shown in Figure 18.

Figure 18: Panel Location on Air Compressor Motor

Remove the access panels by unbolting (2 bolts/panel) from the compressor body.

Remove the machine screw labeled in Figure 19 that attaches the motor brush lead

wires to the copper electrical contact.

Lift and disengage the retaining spring to allow for the removal of the

(also labeled in Figure 19).

Figure 19: Interior of Access Panel

iii. Disengage the retaining spring

ii. Remove machine screw from electrical

contact

Lower Panel

Upper Panel

20

Locate the two access panels for the brushes on either side of the air compressor

panels by unbolting (2 bolts/panel) from the compressor body.

that attaches the motor brush lead

Lift and disengage the retaining spring to allow for the removal of the motor brush

Disengage the retaining spring

Remove machine screw from electrical

21


v. Remove the worn brush and replace it with the new brush. Refer to Figure 20 for

comparison.

Figure 20: Comparison Between a New & Old Motor Brush

vi. Insert the motor brush back into the slotted opening, while holding the retaining

spring so that it does not interfere. Refer to Figure 21.

vii. Release the retaining spring, returning it to its original position against the motor

brush. Refer to Figure 21.

viii. Reattach the motor brush lead wires to the electrical contact; secure it with the

original machine screw. Refer to Figure 21.

Figure 21: Interior of Access Panel without Brush and Spring

Slotted opening for Brush

Electrical contact

New Brush Worn Brush

22


ix. Reinstall the access panels to the air compressor body and tighten screws to secure

(each component is outlined in Figure 22).

Figure 22: Components within Access Panel of Air Compressor Motor

Access Panel

Motor Brush and Machine Screw

Compressor Motor

23

Parts

Below is a table that lists the parts associated with the maintenance procedure. Included in

the list are the corresponding part numbers and costs for reference.

Table 4: Part Identification & Cost

Part Name Part Number

Digital Alarm Box GP-00100-06-ALMBX-00010

Air Tank, 2 Gallon, Vertical GP-00100-03-ARTNK-00010

Air Tank, 2 Gallon, Horizontal GP-00100-03-ARTNK-00020

Air Water Separator Unit, ¼” NPT, 5um, inlet

300 psi, manual drain, metal bowl GP-00100-03-FILTR-00010

Air Water Separator Filter GP-00100—02-ARFLT-00020

Urea Injection Nozzle GP-00100-06-IJNOZ-00010

Suction Lance Kit GP-00100-05-SCNLC-00010

Urea Filter – Suction Lance Kit GP-00100-11-FILTR-00010

Urea Tank Drain Valve, ½” NPT(M), hex socket GP-00100-10-FTTNG-00160

Compressor Pump 12V GP-00100-02-CMPSR-00012

Compressor Pump 24V GP-00100-02-CMPSR-00024

Air Filter Assembly, Compressor Intake GP-00100-02-FILTR-00010

Compressor Air Filter GP-00100-02-ARFLT-00010

Motor Brushes & Springs (kit of 2) GP-00100-11-MBRSH-00010

Please contact Nett Technologies for ordering parts.

24

Troubleshooting

The digital display of your Nett BlueMAX™ System will be activated when an OBD error is

detected. The number displayed indicates the type of OBD error. Recommended action is as

per table 4 below.

Table 5: Troubleshooting

OBD Error Error

Code

MIL Urea Comments

EEPROM 1 On Off Switch of power supply and restart after one

minute. If problem persists, contact Nett.

Drive Unit 2 On Off Switch of power supply and restart after one

minute. If problem persists, contact Nett.

NOX Sensor In 3 On Off

Check the NOX sensor and its connections

including relays and fuses. If problem exists

contact Nett.

MAF Sensor 4 On Off Check the MAF sensor and its connections. If

clogged, clean by blowing air.

Catalyst Temp. In 5 On Off

Check the temperature sensor and its

connections. If problem persists change

temperature sensor.

Dosing Valve 7 On Off

Dismount the urea in tube and inject clean

water into the suction inlet to make the urea

pump prime. If problem persists, contact

Nett.

Internal Heater 10 On Off Contact Nett.

Pump Head Temp. 12 On Off Temperature is above + 85

0 C. Urea pump

cannot work at this temperature.

Pump Frozen 13 On Off

Temperature is below – 50 C. Allow few

seconds after restart. If problem continues,

contact Nett.

Blocked Nozzle 16 On Off

Blocked injection line or nozzle. Use clean

water to unblock the nozzle or the injection

line. If problem persists, change injection line

with nozzle.

Urea Level Sensor 17 On Off Check connections to urea lance. Check filter

at bottom of lance.

Urea Tank Level

– Full

– Low

– Empty

18

18

E

Off

Off

Off

Off

On

On

Refill urea tank.

25

OBD Error Error

Code

MIL Urea Comments

Air-Urea Detection 19 On Off

No air or urea present. Check compressor

fuse, air filter, connections and check air

presence by removing tube. If there is no

urea present OBD error 18 will appear. Check

for presence of urea in tank and all

connections for damage and/or leakages.

Return Line 20 On Off Contact Nett

Any Other Errors Report to Nett

No Power – Check fuses, power supply, main harness connection to urea dosing pump, and alarm

box for OBD codes.

Urea stalactite (white deposits) are visible at the exhaust pipe; report to Nett.

When the system is first switched on, the MIL light appears and stays for 30 seconds indicating

that the system is priming and not ready for use. The light disappears after 30 seconds. When the

system is shut down, the system purges for 30 seconds before shutting down.

IMPORTANT: DO NOT OPERATE THE EQUIPMENT WITH EMPTY UREA TANK; THE EQUIPMENT

WILL NOT START. IF THE EQUIPMENT DOES NOT START EVEN WITH UREA AND AIR PRESENT

CHECK ALL FUSES IN BLUEMAX COMPRESSOR AND DOSING UNIT.

nett bluemax™ scr system...property unit siemens (1999) din v 70070 name aqueous urea solution no...

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